Samples of lyophilised porcine kidney were scanned by photon transmission tomography. The tomographs were used in the selection of sub-samples for subsequent trace element determination by 2MeV PIXE analysis. Major and trace element concentrations for Ca, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Cd and Pb for whole kidney, cortex and medulla are derived. These are discussed, accompanied by sampling factors, to emphasise the need for rigorously enforcing sampling protocols.